Polarizing lenses are used for anti-glare glasses, sunglasses, goggles, corrective glasses, or other glasses (or eyeglasses) in order to block the reflection of the light from the road surface, the wall surface, the snowy surface, the water surface, or other surfaces. Such glasses are worn for outdoor activities, for example, mountain climbing, angling, and playing baseball, driving vehicles, or other purposes. A polarizing lens has a multilayer structure containing a lens body and a polarizing layer through an adhesive layer; on the surface of the polarizing layer, a protective layer is usually laminated.
With respect to the polarizing lens having such a structure, Japanese Patent Application Laid-Open Publication No. 2014-106398 (JP-2014-106398A, Patent Document 1) discloses a polarizing lens comprising a polarizing film provided in a sandwiched manner, wherein a glass lens is provided on one side of the film and a resin lens is provided on the other side so as to form a laminated structure, and the resin lens has a thickness of 0.50 mm or less. The Figures of this document show a polarizing lens having a uniform thickness and being curved at a predetermined curvature.
Japanese Patent Application Laid-Open Publication No. 2010-113147 (JP-2010-113147A, Patent Document 2) discloses a polarizing lens comprising a polarizing plate and a thermoplastic resin layer laminate-molded thereon. The polarizing plate comprises a poly(vinyl alcohol) polarizing thin film and an acetyl cellulose protective film bonded to either side of the polarizing thin film with an adhesive composed of a mixture of an epoxy resin and an acid anhydride. This document discloses that a polycarbonate resin is molded by injection molding or other methods to form a molded resin layer. The Figures of the document show that one of the protective films is curved to form a convex front surface of the lens, the resin molded layer is formed on a concave of the polarizing plate by injection molding to form a flat rear surface of the lens, and the lens has a flat edge face in a circumferential direction thereof.
Japanese Patent Application Laid-Open Publication No. 2011-180266 (JP-2011-180266A, Patent Document 3) discloses a polarizing laminate comprising a linear polarizer, a protective function part (a cast molded sheet, a stretched and oriented sheet, or an extrusion molded sheet having a thickness of 0.25 mm or less) laminated on a first side of the linear polarizer, and a thermal bonding function portion (an extrusion molded thermal bonding sheet) laminated on a second side of the linear polarizer. This document also discloses that a polarizing lens is produced by heat-bending a flat polarizing lens composed of the polarizing laminate to give a curved polarizing lens, inserting the curved polarizing lens into a mold, and injection-molding a backup resin (a polycarbonate resin, a polyamide resin, a polyester resin, a polyurethane resin, a polyacrylic resin, a polycycloolefin resin) to the thermal bonding function portion (a side facing user's eyes) of the curved polarizing lens to form a lens body. The Figures of this document show that a polarizing lens is obtained by injection-molding a polycarbonate resin, a polyamide resin, or other resins on a polarizing laminate bent at a predetermined curvature (a curved polarizing lens) to form a curved lens body with the same thickness ratio.
The polarizing lenses described in these documents have a flat edge face and are thus difficult to fit (or mount) in a groove (or a bezel) of a frame (or a groove of a frame rim). Fitting such a polarizing lens to a frame separates the polarizing layer from the adhesive layer at an edge of the polarizing lens in some cases and reduces the yield and efficient production of polarizing glasses. In particular, for a rigid metallic frame, the polarizing lens is difficult to fit due to low flexibility or bendability thereof, and additionally, the separation (or delamination) easily occurs at an edge of the polarizing lens. With respect to a frame made of a resin such as a cellulose acetate, the resin frame can be softened by heat to easily fit the polarizing lens to the frame. In this fitting operation, need of heating reduces an efficiency of the fitting operation. In addition, the separation as described above easily occurs probably due to softening of the adhesive layer. The polarizing lens is fitted to the frame more tightly, the polarizing layer is separated at an edge of the polarizing lens more easily.
International Publication No. WO2006/040954 (Patent Document 4) discloses a protective film for a polarizing film; the protective film comprises an alicyclic polyamide resin and has a retardation value of not less than 300 nm. This document describes that a polarizing lens is produced by laminating a polyamide layer on either side of a polarizing film through a urethane-series adhesive layer to give a multilayer protective film, bending the multilayer protective film, and injection-molding an alicyclic polyamide resin on the inside of the film.